MAXlum BlackScreen - First practical tests and detailed results
In recent special reports dealing with the “black screen” we have already explained in detail the idea and the principle of “many lumens + dark screen” and we have shown that this method compared to conventional gain screens provides numerous advantages.
YouTube Special: The MAXlum BlackScreen dealing with picture & sound (in German)
It’s here: Maxlum Cine4Home BlackScreen !!
In the meantime a finished series canvas of the “BlackScreen” has entered our test studios – reason enough to conduct a first “real” practical test. After all the theory, we will show what you should keep in mind with regard to installation and what the advantages and disadvantages are. Let’s get started…
1. The right place for the screen
First of all, it is important to find the right place for the screen. It is unfortunately Utopia to think that you can install the BlackScreen wherever you want to and that it will automatically provide a perfect black level and good contrast. As our first special showed, the sun provides so much light energy (thousands of lumens) that even on a white canvas no projector light on earth is strong enough to compete with it. Therefore, it is important to consider the following aspects:
The image, the brightest spot in the room?
In order to transmit the image authentically bright enough for our eyes, it should not be darker than the rest of the room. In practice, this means that in daylight (white) walls should be illuminated by the sun about as much as the screen. This at least applies to the walls that are directly near the screen and at the same time in the field of view. What “happens behind us” can be ignored.
The relationship between image brightness does not only depend on the sunlight in the room but also on the light output of the projector and the image size. The latter is predetermined by the BlackScreen (2m), the former is determined by the projector model. Generally, the brighter the projector, the more light we can have in the room. Therefore, we first have to calculate:
Projector light output (lumens) ÷ Screen Size (m²) x reflection factor = Lux
If you buy e.g. a 3000 lumen projector, this is 3000 ÷ 2.25 x 0.25 = 333 lux. The walls behind / next to the screen should not emit more than 350 lux. In the case of brighter projectors, more lux are possible, up to more than 600 lux. You can quickly identify how bright the walls are “shining” using a lux meter.
If you want to influence the contrast especially positively, you should additionally choose a “shadowy” place for the screen. With regard to measurement, this means that the illumination by the sun of the wall, in front of which the canvas is to be mounted, should be between 50 and 190 lux. This value, too, can be quickly determined by a lux meter.
Last but not least, you have to make sure that the screen is equally exposed to the ambient light and that not for example one part is illuminated by the sun or a ceiling spot, while the other half of the screen is in the shadow.
Observing these basic rules enables you to decide before the installation whether installing the BlackScreen is possible and useful, or not.
Note:
If the pre-analyses concerning measurement confuse you at a first glance, don’t worry: we will soon be publishing detailed step-by–step instructions on how to position the BlackScreen perfectly.
For our first practical test we did not want to make any compromises as far as the image is concerned. This is why we chose two of the brightest Full HD projectors, which you can just about install at home: the Epson EB-Z8000 and the Panasonic PT-DZ6700. With a light output of 6000 lumens, these models are free of the largest room limitations. In this first practical test, we will not only investigate the image characteristics of the BlackScreen but also the qualities of both light canons as far as the image is concerned. Are they good enough at all for cinema projection?
The positioning in our test room
Despite the immense "light power" of the projector, we did not hang the screen “anywhere” but we chose a strategically favourable place in our test room 2. After all, in the near future we also want to test “normal” projectors in combination with the BlackScreen. We want to install the screen in front of our matt white fixed frame screen. It is right next to the balcony door – which comes very close to a typical place in a living room.
In order to optimize the light conditions, there is a white curtain in front of the door. In fact, such curtains are an effective method in order to almost halve the amount of light in the room, without this being noticed by our eyes.
The curtain in front of the balcony door reduces sunlight
The balcony provides an advantage because it has a roof one-meter wide. This prevents the sun directly shining into the room and onto the canvas.
The projecting roof also prevents direct sunshine
With regard to measurement, these room characteristics have an illumination of 100 to 200 lux by sunlight, which is within our recommended limit. The left side is further marked by a complete window front. Should the screen not be convincing under this conditions, then it cannot be so in any other scenario either. Back to top
2. The assembly
As far as the assembly is concerned, the manufacturer did not accept any compromises. The roll- fronted case is compact and square - which makes it particularly flexible for installations. It can for example be completely hidden in a suspended ceiling and is flush with the ceiling when retracted.
The hold- down screws are elegantly covered by a special panel. Without a connecting plate, of course, a conventional ceiling installation with a protruding case is also possible.
The mounting angles are movable and thus it is not necessary to install them onto the wall or ceiling beforehand exactly. Particularly hobby craftsmen are quickly coming to appreciate these possible installation tolerances.
Colour (white, RAL 9003) and shape adapt very well to the usual ceiling colours. Even wall mounting is possible as the angles mounted in the profile rails can also be mounted onto the back of the case.
After assembly, there is still the cabling, as it is a fully motorised screen. Ex factory ca. 3m of cable are led out of the case (above on the right). For those who have longer distances, a cable extension is a must. As far as the correct switches are concerned, you can choose freely, even flush switches for particularly elegant installations are no problem.
3. Processing / Setting-up / First Impressions
After installation the screen rolls out evenly at the push of a bottom. With the built-in tubular motor, the drive is silent and fast enough. The screen automatically switches off with end switches, so that automation is simplified. The entire mechanical design and processing seem to be of high quality, only the white plastic end caps at the end of the case could be a little bit more solid.
In the lowered mode, the heavy canvas cloth attracts positive attention as it seems to be of much higher quality than conventional PVC screens and even in new it hardly smells and is completely gone within a day.
The cloth due to its size is flat without any waves, but typical “dog-ears” appear at the edges, the screen “bends” slightly to the front.
Typical waves on the margin of the screen
This phenomenon can only be eliminated by a special cable pull method but this would have made the screen much more expensive so it was not implemented. The dog-ears could have been covered by framing the screen in black and thus designing the screen optically more elegant. However, the cloth is almost black so areas that are not illuminated sort of behave like a mask. Which approach is better is subject to personal taste. A useful side effect in any case is that the screen because of its darker ground colour is “shape neutral”, which means that it functions as a mask for the aspect ratios 4:3, 16:9 as well as 21:9.
Canvas structure close-up
An objective negative point of the cloth is the dark coating. Although it is concolorous and is matt enough for even light scattering in all angles, you can notice slight differences in surface structure against the light as it seems to be rougher in some places. We will analyse in more detail in the image section whether this affects the image.
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4. The projectors
So that was our first impression. Now we need to deal with the projectors. In order to obtain efficient daylight projection, we have spared no efforts and have used two of the most efficient Full HD projectors for the “inauguration”. In order to be able to compare between different projection technologies, we have chosen an LCD and a DLP model.
Representing LCD projectors is the leading LCD panel manufacturer Epson. The model “EB-Z8000” shines in the truest sense of the word up to 6000 lumens. Also the 5000:1 contrast in this category is very promising if in practice it also proves to be true.
Epson EB-Z8000
The DLP-type is represented by the Panasonic PT-DZ6700. According to the manufacturer, the light output is also 6000 lumens, the contrast is 2000:1.
 Panasonic PT-DZ6700
We start with the Epson Z8000: On the outside, it looks like a spaceship in a science fiction film and with its opulent size can only be integrated more or less discreetly into very huge living rooms.
Inside, not only one UHP lamp provides the necessary light but two. Where there is a lot of light, there is also heat. But as LCDs particularly are very sensitive to too much heat, in the case of this professional projector, it is cooled by liquid.
The LCDs are enclosed within small cooling frames, which are passed through by coolant liquid and thus the dangerous heat is removed from the LCD. We wish that such an effective system could finally be built into conventional home cinema projectors, as problems with dust could be minimised. Looking inside, you can see how the 5000:1 contrast is possible in the technical data: due to marketing reasons, an adaptive iris is supposed to increase the specs. But whether it really works so effectively as in the case of a home cinema projector remains to be seen.
Despite the liquid cooling the projector of course does not belong to the silent wonders within the projector scene. The ventilators are clearly audible when in use, nevertheless they are by far not as nosey as you would perhaps assume.
The Panasonic also uses the indicated 6000 lumens from two UHP lamps, whose light is directed into the light channel simultaneously. Furthermore it also uses liquid cooling in order to keep the DMD chip at a moderate temperature level.
It is much more compact than the Epson, but this has also consequences: after switching it on, it becomes clear that reducing the sound level was obviously not a priority for the engineers, because one has to simply say that the projector is loud. As various other models show, even a projector with 6000 lumens need not to be so loud.
As far as the connections are concerned, it becomes clear that both are designated for professional use. The large number of inputs is realized through high quality forms. Unfortunately, this means that typical home cinema inputs, e.g. HDMI, are missing. The Panasonic has no HDMI inputs at all, you has to implement appropriate converter plugs, the Epson at least has one HDMI connection and thus is a whisker ahead.
We assume that neither of these two devices will rarely make their way into the living room, simply because of their price range (ca. €10,000). But also the technical realisation is in many ways not suitable for living rooms: the Epson is too big, the Panasonic is too loud. But this was not the priority of our test; after all, we wanted to use the maximum potential of the BlackScreen with the Full HD resolution and the 6000 lumens. But are the two devices actually the right ones for this purpose?
4.1 Image options
After switching it on, we activated the image menus and are surprised: the Epson’s image menu does indeed seem familiar to us, but not because of the current home cinema devices à la TW5500, but rather because of the entry level being far below €1000.
Image menu of the Epson EB-Z8000
In fact, the €10,000 projector can only influence image minimally. A gamma equalizer, separate RGB controls for the Gain & Bias as well as a varied colour management are not available.
At least it offers various factory presets on whose adjustments we as users depend. We will be testing how well they turn out, but first we will have a look at the image options of the Panasonic:
Image menu of the Panasonic PT-DZ6700
This model does not offer many detailed opportunities to influence the image as in the case of the current home cinema equivalent PT-AE4000. Nevertheless many important functions are available:
After all, colour temperature as usual can be individually adjusted for bright and dark areas and you can also directly influence the basic colours.
How well can both devices be adjusted? After all we don’t want to pay for the light efficiency required for the BlackScreen with distorted colours...
4.2 Calibration
In the dynamic mode, the Epson Z8000 does truly measure 5700 lumens its factory settings but unfortunately with a green tint that is typical for UHP lamps.
Colour space in the "dynamic" mode
The colour space also does not meet the video standard. Here we have to make imrpovements. First of all, we test the other presets; “Cinema” shows great promise.
 Colour space in the "Cinema" mode
A colour filter moves into the light path following the example of home cinema projectors and causes a much larger colour space, unfortunately much larger than video standard requires. The filter has another side effect: it costs 70% light, only 1800 lumens remain for the Epson Z8000. Less than 2000 lumens? We would also achieve this value with the classical light power editions of the TW3500/4400/5500; the cinema mode, therefore, is not an option.
Colour space in the “sRGB” mode
The colour space of the sRGB mode is adjusted absolutely perfectly, but unfortunately it also uses the internal colour filter and thus loses light. Therefore, it is also not an option.
Calibrated colour space
After several calibration measurements, we succeed in getting the “user” mode close to video standard (as can be seen in the picture above). Although a slight green tint remains, considering the high light output this is not striking and thus negligible.
The situation seems to be quite difficult as far as colour temperature is concerned. In fact, you only have one RGB slider for the basic colours. Nevertheless, we could eventually manage a good closeness to the D65 standard; absolute perfection however was not possible.
In the case of the Panasonic, you can quickly notice colour deficiencies of the Single Chip technology when it comes to colours & a lot of light. In order to achieve more lumens, the green is moved through the corresponding colour segments in the colour wheel towards yellow. This cannot be corrected even with colour management.
 Typical DLP colour space of the Panasonic
You have to live with the green deficiency mentioned above, even though this is maintainable. The Panasonic nevertheless gains ground through its sophisticated RGB controllers that allowed us to adjust colour temperature perfectly to video standard using all brightness levels.
 Colour temperature can be calibrated very well
With regard to colours, the Epson clearly wins the test, the 3LCD technology outclasses the Single Chip competitor. Had one not given away potential because of the bad setting options, even better results would have been possible, especially in colour temperature.
The Epson also clearly wins with regard to brightness: after calibration it still has ca. 4500 lumens net left. Considering the good colour representation, this is a very good performance.
In the case of the Panasonic, things do not look so good: already in the dynamic mode our test device failed the stated of 6000 lumens ex factory, after calibration only 3600 lumens net are left. Considering the dual lamp system and the corresponding sound volume this is rather disappointing.
On the other hand, the Japanese DLP does well when it comes to contrast. The Panasonic 6700 manages to combine the high light output with a native contrast of 1100:1 and the typical high ANSI contrast of the DLP of 500:1.
The Epson, as far as contrast is concerned, looks far worse: its native contrast is only about 500:1; this level is increased to over 3000:1 by the adaptive iris.
Considering the gamma, the better Panasonic setting options pay for themselves. The Panasonic allows for a gamma curve that particularly in the nearly black areas provides enough deep dimensions.
Panasonic: Constant 2.2 gammas with good deep dimensions
In the case of the Epson, we are again at the mercy of factory presets. These also provide a good gamma adaptation, but at the lower level you can only slightly increase the deep dimensions.
Epson: Worse deep dimensions
Especially for the BlackScreen, the practically black area is of utmost importance, as it has a dark basic tint and the penetrating light can quickly contribute to the fact that subtle details cannot be seen any more.
In the case of the Epson therefore a very high light output and exemplary colour fidelity compete against Panasonic’s higher contrast and a better deep dimension picture but less light and paler colours. How does this affect the picture?
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5. Visual impression
In the practical test it becomes clear that both devices have lived up to their promises. In our installation with the BlackScreen they produce excellent image brightness in spite of the dark canvas that is on the level with the rest of the room light.
The image above is not a “sugar-coated” photo montage but does actually reflect the real visual impression! Through the dark basic colour, the contrast seems to be balanced, the maximum light output corresponds to the ambient light and thus does not appear too dark.
The next popular application is video games. Also here the darkness compromise is reluctantly accepted, even more if you want to play together with your friends.
The example shows that trendy multiple colours used in many video games do not miss out. The fun factor is enhanced by the combination of daylight and compared to conventional flat TVs a far better resolution!
Last but not least the most critical application is left: feature films. They often have dark scenes and show a slight contrast, although especially here image depth and black level are of utmost importance in order to create the desired atmosphere.
Also here our projection comes amazingly close to the quality of a good TV. With the right combination of image depth, image brightness, black level and contrast in almost every scene, impressive results can be achieved. The pre-calculations and measurements during the installation were therefore worth it.
Which projector therefore creates the best image? To no small degree this usually depends on your own preferences. At first glance, the Epson Z8000 wins. Its significantly higher light output in combination with the good colours provides a real TV picture; you do not need to accept any compromises with flat screens. On the contrary – other technologies do not allow for such big, bright images with a high contrast, not even in this price range.
Despite all the advantages, the BlackScreen system is not completely free of side effects. A closer look reveals the variations on the surface texture, which we already noticed after assembly. The dark basic colour sometimes causes a kind of “sparkle” in bright parts of the image. This can be noticed particularly in pan shots as the “sparkle” remains steady in the picture despite movement.
Sparkle in bright, homogeneous image parts
The second point of critique concerns the flatness of the picture: the dark basic colour of the BlackScreen is more sensitive to curvatures than a white cloth. This becomes particularly obvious on the “dog-ears” at the sides.
The curved screen edges can be seen in the projection
In the picture above you can see that the waves on the edges are clearly obvious despite image content. Thus you should not enlargen the image so that it covers the whole screen. At least here it becomes clear that a small edge masking the BlackScreen would be useful.
Back to our image comparison: because of its excellent light output and great colours the Epson in is very convincing daylight projection. The Epson profits by the fact that the BlackScreen reduces its original black level through the dark cloth so that the black level under daylight conditions is very good. But a closer look reveals that the black colour is slightly lightened.
Also the perfect deep dimensions in dark areas are to be criticized; you can only work against it by reducing the black level (by increasing the brightness). Once more, the problem is that the projector only provides very few image options.
The Panasonic brings about a very good “TV feeling”, but in direct comparison its low light output becomes obvious; some “pzazz” is missing in the image. Nevertheless its time will come, in the evening.
The ANSI contrast gains more importance: until now it was irrelevant for living rooms, as the bright walls re-reflect a lot of light from the image and therefore significantly reduce the in-picture contrast. The BlackScreen however filters the disruptive stray light up to 80%, and thus the in-picture and the ANSI contrast can be largely maintained. This benefits the DLP Panasonic and its higher native and ANSI contrast. In the dark or in a dark room it reaches a higher level of image plasticity than the Epson. For watching feature films in the evening where sunlight is absent, the maximum brightness plays a minor role and offers clear advantages. You may be really surprised how the “recovery” of the ANSI contrast compensates other projector deficiencies (black level, native contrast). Especially bright scenes appear much more plastic than with home cinema projectors and conventional white screens. The good gamma setting guarantees deep dimensions exactly nuanced; here the Panasonic also scores well.
6. Conclusion
What are the results of our first detailed practical test? First of all, the uncompromising combination of Full HD professional projectors, the BlackScreen, precise installation and planning have demonstrated that large screen projection compared to large screen televisions is in fact a serious alternative even in non-darkened living rooms. Contrast as well as brightness is in no way inferior to flat screens.
Especially noticeable is the image size. True TV with 2m picture width is hardly possible at the moment with plasma or LCD technology, not even in the higher price category of the projectors we showed today. And last but not least, the BlackScreen with its narrow depth is flatter than any TV set.
For a convincing result nevertheless precise planning and choice of components is important: the BlackScreen is not to be mounted in direct sunlight and is to be constantly lightened in order to avoid shadowing effects. As it is currently only available in one size (2m) you have to control image brightness using the light output of the projector. This installation becomes possible from 2500 lumens upwards.
The topic of “projectors” is the most complex in this respect and even in this price range it is not free of compromises. The models we tested are not aiming for high contrast or image perfection as much as the current generation of home cinema oriented devices do. They are not as quiet, beautiful, not so multifunctional, but they mainly focus on just one aspect: light!
The screen itself is very convincing as far as installation flexibility and workmanship are concerned, but one would prefer a mask to conceal waves at the edges and in bright pan shots its rough surface texture becomes apparent through a kind of “sparkle”. You should further make sure to put it up perpendicularly, as waves in the cloth are more visible than in conventional white screens.
The BlackScreen offers a completely new integration of large images in livings room and furthermore offers a lot of potential. Besides, the current limits due to the projectors particularly high price constitute a negative aspect. The screen costs €790, but professional projectors cots many times more that of the current home cinema generation.
For this reason in the next special feature we will search for cheaper “light cannons”, preferably with Full HD resolution. The first candidate has just come in at the right moment: the Mitsubishi HC3900 could become one of the first affordable “BlackScreen compatible” Full HD projectors of the year... Back to top
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